With the continuous development of the liquid crystal display technology, the liquid crystal display device has been more and more widely applied. During operation of the liquid crystal display device, the display is generally accomplished by rotation of the liquid crystal molecules driven by a voltage difference (i.e., a driving voltage) of the data voltage outputted by the source driver and the common voltage outputted by the common voltage output driver. In order to avoid the liquid crystal molecules from being driven by a certain fixed driving voltage for a long time, and the rotational characteristic of the liquid crystal molecules from being destroyed, the polarity (including positive polarity and negative polarity) of the driving voltage needs to be reversed generally, i.e., the polarity of the driving voltage varies alternately between the positive polarity and the negative polarity. As shown in FIG. 1, when the data voltage is higher than the common voltage, the polarity of the driving voltage is positive polarity, vice versa, the polarity of the driving voltage is negative polarity.
During operation of the liquid crystal display device, since the common voltage outputted by the common voltage output driver is generally a constant voltage, in order to ensure polarity of the driving voltage of the liquid crystal molecules to be reversed, the variation range of the data voltage has to be twice of the driving voltage, for example, if the driving voltage is V0, the variation range of the data voltage is 2V0.
In order to ensure the source driver to output the data voltage normally, the maximum working voltage of the source driver has to be 2V0, hence, the maximum working voltage of the display panel has to be 2V0, i.e., the maximum working voltage of the display panel is twice of the driving voltage of the liquid crystal molecules, such that the actual power consumption of the display panel would be twice of the theoretical power consumption.